Ross Garnaut is expecting emissions in China to peak soon and start to fall.

Samuel Cardwell: AAP

China, one of the biggest greenhouse polluters, may yet be one of the best chances the world has of avoiding dangerous climate change, according to climate policy expert Ross Garnaut.

Professor Garnaut, who addressed the University of Melbourne last night, said he was expecting emissions in China to peak soon and start to fall.

This, he said, would pressure Australia and other countries to stand by their commitments to cut emissions further if developing countries did so.

"For 11 years of this century, China was engaged in highly coal intensive and emissions intensive growth," Professor Garnaut said.

"But China in recent years has been introducing a new model of economic growth, but the overall effect of it is to change the relationship between GDP growth and coal use."

Professor Garnaut said China's coal use was going down and if emissions began to fall, it could "bring within reach the world's holding temperature increases to two degrees, or having a reasonable chance of doing so".

"[There is a] very big increase in the share of energy use coming from all of the alternatives to coal - hydro electric, wind, nuclear, solar, gas - all of the alternatives to coal are growing very strongly," he said.

Though Professor Garnaut said he expected the Chinese coal sector will resist cutting its use, he said there were strong forces propelling the government along a cleaner path.

"The problem of domestic pollution is leading to lower life expectancy of people in parts of China with a lot of carbon particulates in the atmosphere," he said.

"And this has become quite a big social and political issue in China and it adds to the reasons why the Chinese government is quite likely to stay the course."

Professor Garnaut said China's switch to cleaner power put more, not less, pressure on other countries to make cuts to emissions.

"It's quite clear that we've got to do a lot more than the 5 per cent that's been talked about," he said.

"We've got to actually honour the international commitments that we've made and the political commitments that have been made by both sides of Australian politics.